Machine for grinding the ends of coiled springs



Jan. 1, 1952 H. F. HEATH 2,580,542

MACHINE FOR GRINDING THE ENDS oF CQILED SPRINGS Filed July 51, 1947 5 Sheets-Sheet l /f/J ATTORNEY.

Jam 1, 1952 H. F. HEATH 2,580,542

MACHINE FOR GRINDING THE ENDS oF coILED SPRINGS Filed July 31,-1947 3 Sheets-Sheet 2 INVENTOR 'M www Jan. 1, 1952 H. F. HEATH 2,580,542

MACHINE FOR GRINDING THE ENDS oE corLED SPRINGS Filed July 371, 1947 5 sweets-sheet s E v ,l v l FIC-`3'0- y .9N mh] e 7p A YE .4 N

l INVENTQR /S//f' ATTORNEY Patented Jan. 1, l952 MAHINE FOR vGRINDING THE ENDSJOF "COILEDSPRINGS iHarold .Frederick Heath, Redditch, England, as-

signor to` W. ..J.1Llewellyn Limited, Redditch,

England Application JulyA 31,1947, Serial No.,.765,0'18 InGreat Britain July 3, 1946 :Section 1,Public Law 690,-August 8,1946 .'Patentexpires July 3, 1966 2 Claims. (01551-118) This invention"relatesl to f a Vmachine forA grinding the endso'f coileci'springs, saidmachine being .o`1"-'the?typehaving 'opposed iuppersand lower :grinding 'wheels :mounted `;on"vertica1 `.sygzindl'es ,journallled in 'verticallyadjustable*carriages and i zontal `plane and having spring receiving openings positioned Ito. `advance ,the .springs between "opposed axially .directed faces of 'the grinding wheels.

The object "of theinvention is .to `provide an improved'form'of fsupportingstructure of 'frame which enables lateral traversing .in the horizontalplane'to be 'effected as: between theugrinding l"wheelson the;one"'hand and the feed plate on the '"other.

In the improved supporting ystructure or frame according v4to the 1 present. invention, "the ,grinding `wheelsare so L'mounted `thatthese are capable of beingftraversed .laterally to .adjust the ldegree of "-overla-pwith' the Aieedplate whilst the' feed plate ismaintained in afxed` position.

'One'of the major advantages of .this arrangem'ent is that 'in' applying Athe lateral traverse. .to

the grinding wheels` this facility is, incorporated in the `machine'without:entailing.additional com plica'tion lt willib'e appreciated that Ysince the grinding wheelsaregrequired to `be `adjustable in the"vertical-.direction to vary'jtheir spacing, the

drive to thegrinding wheels must in any case be such as to allow'this adjustment to ...take place and therefore by applying the additional .facility for transverse adjustment to thegrinding wheels. The inherent ability "of the drive means to .the grinding wheels to 'admit 'of' bodily.` adjustment thereof `is` utilised efficiently in. vextending the scope-of the `adjustment which can. be carriedout Onthe other`-ha1id. thefeed plate .which is normally required to" be rotated. at .a comparatively slow' speed-such `as will, .permit the insertion -o'f springs-into 'springreceivng openings thereir1'f'byA *hand^vfliilst""`the plate is `rotatin .is necessarily driven through a reduction` gear and consequently ithe application' of the facility Vfor lateral: traverse 'tofrthe'ffeed plate itself would involve "considerable complications in the drive mechanisml "therefor, flih-isis-entirely avoided by the. present sinvention.

A `further advantagerofithejinvention is that by maintaining .the 1 feed platezin atxed .position relatively .to ethe supporting structure of the machine asa whole, theyoperator always ,performs precisely the same movementin insertinglsprings into the feed plate, this factor being ofgconsiderableimportancein achieving a. high productivity witlilow` grade labour. v

.An embodiment of the present invention-will nowV be described with referenceto the drawings in-lwhich:

`Figure .1: isa .viewofamachine `constructed in zal) accordance with "the invention 'in front elevation. Figure 2 is` a viewofthesame `machine in Aside `elevation `Viewed from the left handside` of `Fig-- ure 1.

Figure3 is a sectional plan view, the section beingtaken onthe line 3-3 of Figure `l.

Figure 4 isase'ctional elevational view 4on the line 4'4 of Figurefand Figure 5 is a fragmentary view in sectlon show- `ing the construction of a'feed wheel bush.

` The machine is `supported by a frame. the lower part of which comprises a table-like top'lOgsupported at each side by legs I|- themselves connected together attheir'lower endsby a supporting base plate' I2 for a driving, motor.

The rearpart'offthej table carries a vertically extending support plate I3 forthe grinding `wheel motors which is suitablynstiffenedby means of a longitudinally extending -rib I4 at l,the rear of theV plate.

Atone side ofthe table is positioned a bracket which has vertical arms I5 and |`6 extending above and below and to one sideof the table, each arm terminating in abearing which carries the feed Wheelshaft H.

`The feed plate l8 is supported on andkeyed to the shaft I1 and rispositioned above the `upper bearing I9 at the endo'f the bracket arm I5. The shaft l1 extends through the lower bearing 20 at the end 'of the'bra'cketarm I6 `and -is there providedwith a bevel gear (il engaging the second `lzievellgearlii. Whi'chis Tdriven lso as to rotate the feedl plate I8.

"The feed plate has ainumber of circular holes 2 Ispaced-around its peripheral margin, "the holes extending through theplate Withtheir axes parallel to the 1feed-pla`te faxis.

'Each of the holesfisprovidedvwith a detachable and replaceable bushfsuch as that shown at 22, the :'internalldiameter `oi' .which corresponds with the external diameterof the .spring whichitis required to grind. .'JThe'- bushes are .secured by means fof grubscrewsi23 :in `the feedplateiextending radially inwards and y accessible `from the circumferential -edge of the `feed plate.

The upper and lower grinding wheel motors 24 and .25 are .eachsupported upon `separateupper and lowercarriages :2 l` and 21. The carriages ,are slidably mounted on ,thesupporting plate `i3 by means `of a dovetailedrib 28extendinglengthwise along .the latter, .engagingin-.groovesof undercut sectionin the, former.

`To secure each carriage in position :clamping screws 29 i and 30 ,are provided lfor upper and lower carriages respectively, `the ,inner .ends of whichforce plates such as that shown atril intel-posed between one.side o'f the undercut groove and the dovetailed section rib into clamping engagement with the latter. y In order to permit accurate adjustment of each carriage and its associated motor and grinding wheel in a vertical direction traversing screws 32 and 33 are provided for upper and lower carriages operated respectively by hand wheels 34 and 35.

The screws 32 and 33 lie within a rectangular section slot cut along the centre of the dovetailed section rib 28 and are prevented from axial movement relative to the supporting plate I3 by means of collars 36 and 31 for the upper screw 32 and by means of collars 38 and 39 for the lower screw 33 disposed on the screws 32 and 33, respectively, on opposite sides of the transverse supporting plate I3 and piece 4I), respectively. The ends of the screws remote from the hand wheels pass through internally threaded circular openings in `lugs 42 integral with the carriages.

The grindingwheel motors 24 and.d 25"'ar positioned so thattheir spindles lie alongthe same vertical axis`,that of the upp'er'grinding wheel motor projecting in .a downward direction and there carrying the upper grinding wheel .43 and that of the lowergrindingv4 wheel'motor "projecting in an upward directionfand `there` carrying the lower grinding wheel 44."

AThe grinding wheels 43 and 44 have opposed axially directed grinding. faces Vwhich are spaced from eachother byan amount depending upon the length of the springs to 'be ground and by the amount of metal which it is required to grind from the ends ofluthe springs; the arrangement of the grinding wheels and the Vfeed plate being such that a portion of the feed plateis located between the said faces ofthe grinding wheels.

Preferably the 4grinding wheels are rotated in the same direction so that 'there is no tendency for the springs` held in theA feed plate lto become deflected from the vertical.l

Grinding Awheels of known construction'which may be employed are usually constructed so that an annular grinding elementl4 5 is supported bya metal hub element48. `In orderto` ensurejthat full use is made of the availablegrinding face and further to ensureV that when springs of large diameter are being groundportions of these do not project beyond -the inneredge ofthe annular grinding element the centres of the grinding wheels may be adjusted laterally with respect to the centre of the feed plate by means o f traversing screw 41 which slides the supportingf plate I3 and grinding wheel assembly securedthereon laterally over the top plate IIJ ofthe tablel so that the said assembly moves in relation to, the feed plate I8. Separate traversingscrews 41...are provided at each side of the tablesupported in brackets 48 having threaded circular openings through which screws extend.

The lower grinding wheel motor carriage 21 carries on one side a bracket 49 which serves to support a guide plate 50 for locating and supporting the lower ends of the springs placed in the feed plate. tending portion I provided with slots 52 through which pass securing bolts fastening it'to the bed plate, the bracket being capable of vertical ad` justment, the securing bolts sliding in the slot, and a second portion'53 of approximately annular form on the upper face of which is carried the lower guide plate 5I). The lower guide plate 50 is itself of annular form and has a cutaway portion where it meets the edges of the lower grinding wheel.

`The edges 54'and 55 'ofthe cut-away portion of the guide plate are of circular form and have the same curvature as the edge of the'lower 'grinding Vwheel-*and are vspaced.therefrom by a into Ygrinding engagement with the grinding The bracket has a downwardly ex- Y wheel.

In the case of the upper grinding wheel a somewhat similar arrangement is provided comprising an upwardly extending bracket portion 56.secured tothe upper carriage 26 and supporting an upper guide plate 51. The upper guide plate V51 is much shorter than the lower guide plate since its function is confined to guiding the upper endsvof the springs immediately prior to tgreater than. the length of the springs which it is required `to grind, the inclined portio'nleading to and. terminating ina portion which is adjacent the edgeof theupper grinding'wheel andis there parallel and flush'with the lower face of the upper grinding wheel so that the springs can readily pass intogrinding engagement with the latter. .l The edge of the .upper guide plate adjacent the upper grinding `wheel is as in the case of the lower guide plate of curved'formation and spaced from the grinding vwheel by a small clearance. In order to deliver the springsfrom the Vmachine when their ends have been ground there is an opening provided lin the lower guide plate positioned so that ysprings carried 'by the feedV plate pass over it'aftejr, leaving the grinding wheels. Beneath the opening there is provided a chute 59 down which the'springs fall into asuitable l container.

The drive for the feed plate is derived from an electric motor `lillhoused beneath the table and `supported uponthebed plate I2, the motor driving the feed platefshaft I1 through a pair of bevel gears 6I and 62 and a preceding reduction gear box 63 and flexible coupling 64.

The motor 60 may also drive a suitable suction device 65 through an endless belt 65, the suction device being connected by a duct 81 to a suitable hood 68 rpartly surrounding the grinding wheels so that the grinding dust is thereby extracted downthe duct. The reduction gear box 63 is such that speed of rotation of the shaft I1 is reduced to a conveniently low value, for example, about four revs. per minute so that an operator can readily insert vby hand springs into the openings around the periphery-of vthe feed plate. Y

In order to re-face thegrinding faces of the grinding wheels after these have been in use for a considerable period'a diamond facing tool 69 may be provided' carried at the end of the pivotal arm 10 secured in a pivotal mounting at one side of the supporting plate I3 so that it can be swung round when required and operate between the grinding wheels, opposite ends of the tool engaging upper and lower faces of the lower and upper grinding wheels respectively.

I claim:

l. In a machine for grinding the ends of coiled springs, the combination of a supporting structure, including a table, bearing means at one side thereof, a vertical spindle supported by said bearing means, a horizontal feed plate mounted on said spindle, said feed plate having spring receiving openings and extending over said table, means for rotating said feed plate, an upwardly extending carriage support slidably mounted on the upper face of said table for movement towards and away from said spindle, means for effecting and controlling said movement, a pair of vertically spaced carriages sldably mounted on said support, said carriages having respective opposed grinding wheels between which the feed plate extends, means on said carriages for driving said grinding wheels, and said support having means for adjusting and controlling the relative vertical position oi the carriages thereon.

2. In a machine for grinding the ends of coiled springs, the combination of a supporting structure, including a table, bearing means at one side thereof, a vertical spindle supported by said bearing means. a horizontal feed plate mounted on said spindle, said feed plate having spring receiving openings and extending over said table, means for rotating said feed plate, an upwardly extending carriage support comprising a base plate slidably supported on the upper face of the table for movement towards and away from said spindle and an upwardly extending bed plate formed with a vertical guide, a pair of vertically spaced carriages slidably mounted on said guide, said carriages having respective opposed grinding wheels between which the feed plate extends, means on said carriages for driving said grinding wheels, means for adjusting and controlling the relative vertical position of the carriages on the guide, and, a traversing screw device mounted on said table and engaging with said base plate to adjust and control the position thereof with respect to said table, whereby the degree of overlap between the feed plate and the grinding wheels can be varied whilst maintaining the feed plate in a xed position.

HAROLD FREDERICK HEATH.

REFERENCES CITED The following references are of record in the le of this patent:

France Mar. 28, 1938 

